This invention relates generally to gas turbine engines and more particularly, to a pulse detonation system for a turbofan engine.
Variable cycle turbofan ramjet engines may be used to provide aircraft flight speeds between low subsonic Mach numbers to high supersonic Mach numbers of about Mach 6. Known engines, as described in U.S. Pat. No. 5,694,768, include a core engine system and a dual mode augmentor. The dual mode augmentor provides additional heat to exhaust airflow exiting the core engine system to increase engine thrust. The core engine system provides power to drive a fan assembly and typically includes in serial, axial flow relationship, a compressor, a combustor, a high pressure turbine, and a low pressure turbine. The dual mode augmentor is positioned downstream from the core engine and receives air from the core engine and a bypass duct surrounding the core engine.
Known engines can operate over a wide range of flight speed operations if several different combustion systems are utilized. During flight speed operations from take-off to approximately Mach 3, the core engine and an engine fan system provide airflow at a pressure and quantity used by the augmentor to produce thrust for the engine. However, augmentor performance may be limited by the constraints of existing engine components. More specifically, at least some known engines include a conventional bluff centerbody that extends aftward from the core engine and enables the engine to achieve pressure ratios necessary for engine operations.